Naruto: I am Uchiha Shirou

Inside the cave, a pair of bloodshot eyes stared intensely at the entrance. Whoosh, whoosh!

A flurry of sharp kunai flashed by, embedding themselves into the hard rock walls around the cave entrance. However, when the strange man saw that the first thing to come in wasn't a person but rather a heap of kunai tied to sizzling explosive tags, his pupils suddenly contracted.

"None of them? Haha, in that case, I'll just charge out and kill them all!"

Boom!

In the next moment, a terrifying explosion erupted inside the cave, coinciding with the thunder in the sky.

"He's coming out!"

With a loud crash, as the figure emerged, Uchiha Mikoto shouted a warning. But upon seeing the figure rushing out of the cave, Uchiha Shirou's expression revealed a sense of confirmation. As expected—Mikoto's intel matched exactly what he had imagined.

"Haha!"

The monstrous figure that charged out laughed maniacally, terrifying black markings spreading across its face, visible to the naked eye, still growing and evolving into a full-fledged monster. This wasn't a tattoo—it was a Cursed Seal!

"The Cursed Seal! A natural Sage Body!"

Upon seeing the figure, Uchiha Shirou showed a hint of excitement. Meanwhile, Uchiha Mikoto, standing beside him, gasped, "Shirou, you know about this?"

At that moment, seeing the monster, especially the black markings continuing to spread, Shirou shouted:

"I've heard similar rumors. Let's finish this quickly—don't give him time to let the Cursed Seal evolve."

Without hesitation, the two acted in perfect harmony, leaping onto two large trees. The monster, upon spotting its targets, let out a crazed, bloodthirsty laugh.

"Haha, blood! I want your blood!"

The frenzied monster charged directly at Uchiha Mikoto, while Uchiha Shirou immediately formed hand signs on the other side.

Zzzzz…!

A sharp sound echoed as steel wires snapped into place. The monster had fallen right into the pre-arranged steel wire trap. However, under the power of the Cursed Seal, the monster roared, breaking through the tough, sharp wires one by one.

At that moment—

"Fire Style: Great Fireball Jutsu!"

Shirou quickly gathered chakra in his throat and spewed out a massive fireball, aiming directly at the monster's back.

"Shirou!"

Seeing this, Uchiha Mikoto finished her hand signs and spewed out an even larger fireball than Shirou's.

"Fire Style: Great Fireball Jutsu!"

Two massive fireballs, one from the front and the other from the back, closed in on the monster. At such close range, the monster had no chance to dodge. More importantly, it had no intention of dodging. Instead, it roared and charged straight into the fireballs.

Boom, boom!

The fireballs exploded in the rain, while the thunder and lightning in the sky masked the sounds of battle. Explosions from the explosive tags and ninjutsu echoed through the forest. In the aftermath of the destruction, the monster had fully transformed, no longer resembling anything remotely human.

"Damn it! This monster has evolved to such a strong state!"

Panting heavily, Mikoto stood on a tree branch, staring intently at the distant monster. Shirou, on the other side, frowned, recalling something. In the original timeline, Orochimaru only discovered Jūgo's existence later, leading to the development of the Cursed Seal. This clan didn't possess a kekkei genkai but rather a special Sage Body constitution. Unable to control their absorption of natural energy, they would go berserk—emotionally unstable.

Realizing this, Shirou made a quick decision and shouted:

"Sister Mikoto, use genjutsu! His emotions are unstable. He can't control this power—use genjutsu to draw out his inner fear!"

With their natural trust in each other, Mikoto didn't hesitate. Her Sharingan, with its two tomoe, spun rapidly as she formed hand signs.

"Genjutsu: Hell Viewing Technique!"

In an instant, the monster, drenched in the rain, met Mikoto's spinning Sharingan, and its pupils trembled violently. Soon, its deepest fears began surfacing.

"No! I didn't kill everyone! Don't chase me away... please, don't..."

Countless memories flooded his mind, and the monster roared in madness, clearly gripped by intense fear. From his frantic words, it was clear—he had lost control, killed the people of his village, and been cast out.

As his mental state became increasingly unstable—

"Now's our chance!"

Seeing the monster's breakdown and frantic cries, Shirou seized the moment. He deftly threw kunai, each tied with explosive tags, aiming precisely at the monster's mouth and throat, its vital points.

Boom, boom!

As the explosive tags detonated, the monster's frenzied roars were drowned out by the explosions. Mikoto let out a muffled groan, clutching her eyes in pain. Using genjutsu had drained her mental and ocular strength, and blood tears began to flow from her eye sockets.

Meanwhile, Shirou took advantage of the chaos, drawing his ninja sword and disappearing into the smoke.

"I didn't… kill everyone… I didn't…"

Squelch!

Blood splattered as a ninja sword pierced through the monster's throat. The creature's body, already half-destroyed by the explosions, continued to rasp weakly.

"Forbidden Technique: Chimera Jutsu!"

Through the smoke, Shirou activated a forbidden technique sealed in his mind for twelve years. He raised one hand, revealing a unique rhombus-shaped cursed mark in his palm, pressing it onto the monster's forehead. Instantly, the cursed mark generated a powerful suction force, continuously absorbing the monster's unique Sage Body power.

Visibly, the monster's transformed body began to revert, revealing its original appearance—a withered old man, white-haired and gaunt, with no trace of chakra, yet after absorbing natural energy, he had transformed into a monster.

"Shirou!"

With a loud shout, the smoke gradually cleared, and Mikoto rushed in, filled with concern. But when she arrived, what she saw was a mutilated body pinned to the ground by a ninja sword through its throat.

"I didn't… kill… everyone…"

The rain washed over the scene, the ground soaked with blood, as the old man rasped his final words. His pupils began to lose focus. Shirou, panting heavily, shook his hand, his expression serious, though inwardly, he was deeply shocked.

To think that this person was just an ordinary old man with no chakra. This wasn't Jūgo, who naturally had the strength of a Jōnin. This old man, with the Cursed Seal's Sage Body, was terrifying indeed.

"Sister Mikoto, the intel must be wrong. If we hadn't brought enough explosive tags, we might not have made it out of here."

Despite Shirou's remark, Mikoto's Sharingan remained fixed on the lifeless figure, her gaze intense. Shirou sighed as the rhombus-shaped cursed mark on his palm gradually faded, leaving faint cursed seal markings under his skin before disappearing completely.

The perfected Chimera Jutsu could absorb and fuse with bloodline limits, though this perfected version required considerable time and genetic stability medication to allow the body to adapt. Although perfected, the technique still required resources. Thinking of this, Shirou cursed inwardly.

His original plan had been to target a Uchiha with an awakened Sharingan, as the bloodline rejection would be minimal. But the Cursed Seal Sage Body was a rare and precious opportunity. Moreover, he wanted to test a hypothesis—and it just so happened that this could be used in his plan involving Tsunade.

With this thought, Shirou's expression became serious.